The present invention relates to a wafer for use in a magnetic head capable of reading and writing on a magnetic medium, and to a magnetic head produced from such a wafer. More particularly, the present invention relates a wafer for a magnetic head, which is excellent in heat transferring property, so that the temperature is less risen during reading or writing, and to a magnetic head produced from such a wafer.
In such a conventional type of a magnetic head, thin magnetic films such as an insulating layer, a magnetic shield film, a bottom pole and a top pole; an MR element; a gap layer; a coil layer and an overcoat are formed on a surface of a substrate formed of, for example, an alumina-titanium carbide and the like.
The insulating films such as the insulating layer, the gap layer and the overcoat are usually formed of alumina.
With the above conventional magnetic head, the insulating films such as the insulating layer, the gap layer and the overcoat are formed of alumina, as described above. Therefore, the conventional magnetic head suffers from problems of a lower heat conductivity, a poor heat transferring property and an instability of the characteristic of the magnetic head due to a temperature rise. Particularly, when the magnetic head includes an MR element, there is a disadvantage that the temperature rise is significant, whereby the motion of the MR element is unstable, because the MR element is a reading element. Another problem is that because the insulating layer is formed of alumina, when the surface of the magnetic head is polished at a finishing step, only the alumina material is polished in a larger amount to produce a difference in level, for a reason that the alumina material is softer than another material. As a result, the gap between a medium and a recording/regenerating element is widened, thereby causing a reduction in output. Further, the conventional magnetic head has a disadvantage that it is poor in water resistance.